解题思路:(1)运用加法结合律简算;
(2)运用加法交换律简算;
(3)先把48分解成12×4,再运用乘法结合律简算;
(4)(5)运用乘法分配律简算;
(6)根据除法的性质简算.
(1)1234+700+300,
=1234+(700+300),
=1234+1000,
=2234;
(2)26+(89+74),
=26+74+89,
=100+89,
=189;
(3)48×25,
=12×4×25,
=12×(4×25),
=12×100,
=1200;
(4)85×199+85,
=85×(199+1),
=85×200,
=17000;
(5)69×27+27×31,
=(69+31)×27,
=100×27,
=2700;
(6)700÷4÷25,
=700÷(4×25),
=700÷100,
=7.
点评:
本题考点: 整数四则混合运算;运算定律与简便运算.
考点点评: 完成本题要注意分析式中数据,运用合适的简便方法计算.